Modern vehicles are increasingly able to interact with vehicle occupants via speech. The vehicle occupants can speak verbal commands to the vehicle and the vehicle may respond by changing some aspect of vehicle operation or providing information to the vehicle occupant, such as navigation directions. But the vehicle receives verbal commands that may involve a wide range of different subjects or vehicle functions, which may be challenging to interpret.
To differentiate one subject or vehicle function from another, the vehicle usually listens for a subject prompt that causes the vehicle to select one vehicle function over another. For example, when a vehicle occupant is looking for a point of interest (POI), the vehicle listens for the words “point of interest” to indicate that the vehicle should identify the location of a POI for the vehicle occupant. Or if the vehicle occupant wants navigation directions to an address, the vehicle may listen for the word “address” before generating the directions. However, vehicle occupants may not intuitively know they are requesting a POI or address such that they can include the words “point of interest” or “address” with their request. Or the vehicle occupants may not know that the words “point of interest” are used to instruct the vehicle to find a particular place. It would be helpful for the vehicle to recognize and differentiate between spoken requests that invoke different vehicle functions without explicitly receiving verbal commands to do so.